Ah, gotcha. Thank you for letting me know!
It’s done after, and I tested without cloning. Looks like the issue is still present then. So I apologize for the misplaced support question!
Thanks for looking into this, Jeroen!
My client has clarified that it’s specifically when they clone a post made in the classic editor then convert it to blocks. With that in mind, I’m guessing this is more of a support question for the Classic Editor plugin, am I correct in thinking that?